Macmillan encyclopedia of sciences : The Earth
New York : macmillan Library reference USA, 1997,
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Encyclopedia of earth sciences; Volume 2
E. Julius Dasch, editor in chief
MacMillan Reference USA, 1996
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Macmillan encyclopedia of sciences : Life on Earth
New York : Macmillan Library Reference, 1997,
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Encyclopedia of knowledge : volume 1
Grolier Incorporated, 1991
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Encyclopedia of bioethics : volume 1
Warren Thomas Reich, editor in chief
Simon & Schuster Macmillan, 1995
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